Brad Stevens says "somebody made a mistake" leaving Jayson Tatum off All-Rookie first team ballot

Boston Celtics v Cleveland Cavaliers - Game Four

Jayson Tatum has been honoured for a terrific first year in the league with the Boston Celtics by being selected to the All-Rookie first team.

He's joined on the list by Ben Simmons, Donovan Mitchell, Kyle Kuzma and Lauri Markkanen.

The 20-year-old becomes the first Celtics player to receive the nod since Paul Pierce in 1998-99.

Tatum, however, missed out on joining Philadelphia 76ers point guard Simmons and Utah Jazz star Donovan Mitchell in receiving a unanimous selection as one voter chose not to include him on his first-team ballot.

Instead, he placed the small forward on the second team, strangely becoming the only voter to do so.

After an impressive regular season, the Duke product has taken his game to new heights in the playoffs, which makes this decision even more absurd.

When told about Tatum being left off one of the first-team ballots, Boston head coach Brad Stevens couldn't understand it and believed there could only be one explanation.

“Somebody made a mistake,” he told reporters.

It's unclear which voter made the decision but the league will release this information in due course and there's no doubt that Celtics fans are waiting to call out that individual.

Unlike many of his fellow rookies, the youngster has been part of a championship-contending team and has played an important role all year.

The injury suffered by Gordon Hayward in the season opener meant that the Celtics had to lean on Tatum more than they expected and he didn't disappoint.

For a team that won 55 games, he averaged 13.9 points and 5.0 rebounds while shooting 47.5 percent from the field and 43.4 percent from three-point range.

Boston Celtics v Cleveland Cavaliers - Game Four

He led all rookies in three-point field goal percentage and ranked eighth in the league overall.

When Kyrie Irving's season came to an end in April after he underwent knee surgery, Boston needed even more from their rookie and once again he's stepped up to the plate.

Last year's number three overall pick has played a major role in their run to the Eastern Conference Finals, leading the team in scoring with 18.0 points per game.

His campaign could yet get even better as the C's are just two wins away from reaching the NBA Finals for the first time since 2010.

For a first-year player to be the leading the scorer on a team competing for the title deep into the playoffs is no easy feat.

It's another indication of just why he deserved to be a unanimous choice for the All-Rookie first team.

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